var gewAffineTransform = {};
gewAffineTransform.rotatePoint = function(point, center, axis, angle)
{
  var inverse_center = new gewVec3(-center.x, -center.y, -center.z);
  var rot_matrix = gewMat4.getRotate(axis, angle);
  var inverse_tran_matrix = gewMat4.getTranslate(inverse_center);
  var tran_matrix = gewMat4.getTranslate(center);
  var matrix = tran_matrix.mul(rot_matrix);
  matrix = matrix.mul(inverse_tran_matrix);
  matrix.mulVec3(point, point);
};